$OpenBSD: patch-asyncsendto_c,v 1.1 2016/09/10 13:03:42 ajacoutot Exp $
--- asyncsendto.c.orig	Sat Sep 10 12:01:40 2016
+++ asyncsendto.c	Sat Sep 10 12:01:47 2016
@@ -6,6 +6,7 @@
  * in the LICENCE file provided within the distribution */
 
 #include <sys/types.h>
+#include <sys/select.h> /* fd_set */
 #include <sys/socket.h>
 #include <sys/time.h>
 #include <sys/queue.h>
